On a very rough-and-ready basis we might define an eccentric as a man who is a law unto himself, and a crank as one who, having determined what the law is, insists on laying it down to others. An eccentric puts ice cream on steak simply because he likes it; should a crank do so, he would endow the act with moral grandeur and straightaway denounce as sinners (or reactionaries) all who failed to follow suit. Cranks, at their most familiar, are a sort of peevish prophets, and it's not enough that they should be in the right; others must also be in the wrong.
Louis KronenbergerIf it is the great delusion of moralists to suppose that all previous ages were less sinful than their own, then it is the great delusion of intellectuals to suppose that all previous ages were less sick.
Louis KronenbergerOurs must be the first age whose great goal, on a nonmaterial plane, is not fulfillment but adjustment; and perhaps just such a goal has served as maladjustment's weapon.
Louis Kronenberger